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Hive QA commented on HIVE-6189: ------------------------------- {color:green}Overall{color}: +1 all checks pass Here are the results of testing the latest attachment: https://issues.apache.org/jira/secure/attachment/12623031/HIVE-6189.3.patch {color:green}SUCCESS:{color} +1 4925 tests passed Test results: http://bigtop01.cloudera.org:8080/job/PreCommit-HIVE-Build/916/testReport Console output: http://bigtop01.cloudera.org:8080/job/PreCommit-HIVE-Build/916/console Messages: {noformat} Executing org.apache.hive.ptest.execution.PrepPhase Executing org.apache.hive.ptest.execution.ExecutionPhase Executing org.apache.hive.ptest.execution.ReportingPhase {noformat} This message is automatically generated. ATTACHMENT ID: 12623031 > Support top level union all statements > -------------------------------------- > > Key: HIVE-6189 > URL: https://issues.apache.org/jira/browse/HIVE-6189 > Project: Hive > Issue Type: Bug > Reporter: Gunther Hagleitner > Assignee: Gunther Hagleitner > Attachments: HIVE-6189.1.patch, HIVE-6189.2.patch, HIVE-6189.3.patch > > > I've always wondered why union all has to be in subqueries in hive. > After looking at it, problems are: > - Hive Parser: > - Union happens at the wrong place (insert ... select ... union all select > ...) is parsed as (insert select) union select. > - There are many rewrite rules in the parser to force any query into the a > from - insert -select form. No doubt for historical reasons. > - Plan generation/semantic analysis assumes top level "TOK_QUERY" and not top > level "TOK_UNION". > The rewrite rules don't work when we move the "UNION ALL" recursion into the > select statements. However, it's not hard to do that in code. -- This message was sent by Atlassian JIRA (v6.1.5#6160)